1. Technical Field
The present disclosure relates to a charged particle beam apparatus and a method for forming an observation image.
2. Description of Related Art
There has been known a focused ion beam apparatus for observing a surface of a sample such as a semiconductor device (for example, see JP-T-2009-517840). Generally, the focused ion beam apparatus includes an ion beam column that irradiates the surface of the sample with a focused ion beam, a detector that detects the amount of secondary electrons emitted from the surface of the sample by the irradiation of the ion beam, and an image forming section that forms an observation image of the surface of the sample based on the detected amount of the secondary electrons. The ion beam column sequentially irradiates the surface of the sample corresponding to a pixel of the observation image with the focused ion beam.
The image forming section forms the observation image of the sample based on a scanning signal output to the ion beam column and a detection signal input from the detector. The scanning signal represents a signal indicating the relationship between time and a pixel relating to irradiation of the ion beam, and the detection signal represents a signal indicating the relationship between time and the detected amount of the secondary electrons. The image forming section sets luminance corresponding to the amount of the secondary electrons for the pixel based on information about the pixel relating to irradiation of the ion beam at a specific time in the scanning signal and information about the amount of the secondary electrons detected at the specific time in the detection signal. In this way, by setting luminance for all pixels, the observation image is formed.